Medical imaging often includes creating images of regions of the human body for clinical purposes, such as examination, diagnosis and/or treatment. These images may be acquired by a number of different imaging modalities including, for example, ultrasound (US), magnetic resonance (MR), positron emission tomography (PET), computed tomography (CT), mammograms (MG), digital radiology (DR), computed radiology (CR) or the like. In a number of example medical imaging workflows, such as in the case of a picture archiving and communications system (PACS), an image study for a patient may include one or more acquired images of the patient along with information that may reside with or otherwise accompany the images. This information may include, for example, a study identifier as well as patient information such as the patient's name, demographic information, medical record number or the like. The information may also include, for example, an indication of the modality that acquired the images of the study, the body region depicted in the images and/or the medical facility where the modality acquired the images. Once a patient study has been created, the study may be stored in the database of a central storage device. The images of the patient study may then be accessed and viewed via a dedicated viewer, such as a PACS workstation.
Medical images are frequently formatted in accordance with the digital imaging and communications in medicine (DICOM) standard. The DICOM standard generally requires the use of relatively complex code libraries. Additionally, the DICOM standard allows the utilization of a relatively large number of image compression algorithms and pixel representations. As a result, any viewer that is to process DICOM images must be configured to implement the complex algorithms that are necessary to interpret images formatted in accordance with the DICOM standard as well as all of the image de-compression algorithms allowed by the DICOM standard. Additionally, any viewer that is to process DICOM images must be able to properly interpret the plurality of different pixel representations allowed by the DICOM standard. As such, a viewer that is to process DICOM images may be quite complex.
As noted above, various algorithms may be utilized to compress DICOM images. As a result, the compressed images may not be manipulated in a consistent manner. For example, a server configured to process DICOM images may not consistently and in a computationally inexpensive manner supply rectangular sub-areas within an image to a viewer, as some of the compression techniques allowed by the DICOM standard do not provide effective techniques for extracting such sub-areas. Indeed, in some instances, the entire image would have to be decompressed, clipped and re-compressed in order to supply a rectangular sub-area, thereby resulting in a computationally expensive process.
DICOM images may be grouped in studies. Over the course of time, a patient may have undergone one or more medical examinations, thereby resulting in one or more studies. A medical imaging viewer generally displays information from one or more studies belonging to the same patient. However, the DICOM standard does not allow for an explicit definition of the logical structure of a study. Rather, a medical provider or other users of a medical imaging system must inspect every image of a study so as to deduce its logical structure, such as by determining the identifier that forms part of a DICOM image. In this regard, two images may be determined to belong to the same study if and only if the identifiers of the two images are identical. As a result, DICOM viewers are generally relatively slow to reveal the complete study structure to the user as the viewer is required to process each and every image in a study in order to determine the respective identifiers and, in turn, the study structure.
In order to define the logical structure of a study of DICOM images, servers have been developed to process the DICOM images and generate the logical structure of the images of a study. While the server is able to provide the DICOM images along with the logical structure of the DICOM images, the server also generates and stores a significant amount of meta-information that must also be provided to a viewer if the viewer is to present the study structure without having to parse each image in the study. Thus, the meta-information may refine or, in some instances, replace the DICOM structural information that was provided along with the study. This meta-information generally has a proprietary format that is readable only by complex specialized proprietary libraries. As such, viewers are required to have such proprietary libraries if the viewer is to make use of the meta-information. Such a specialized proprietary library generally is of a considerable size and complexity, thereby limiting its portability.
DICOM images may therefore be reviewed by dedicated DICOM viewers that are configured to process the images in accordance with the DICOM standard and, in some instances, in accordance with proprietary meta-information that is provided along with the DICOM images. As a result of the amount of data that must be transferred to the DICOM viewers in terms of image data and the associated meta-information as well as the complexity of the image processing required at such DICOM viewers, the viewing and processing of DICOM images is generally limited to dedicated viewers with limited, if any, portability.